1 files changed, 12 insertions, 2 deletions

diff --git a/lib/Target/X86/AsmParser/X86Operand.h b/lib/Target/X86/AsmParser/X86Operand.h
index 9f1fa6c65907..33eff14b8215 100644
--- a/lib/Target/X86/AsmParser/X86Operand.h
+++ b/lib/Target/X86/AsmParser/X86Operand.h
@@ -62,6 +62,10 @@ struct X86Operand : public MCParsedAsmOperand {
     unsigned Scale;
     unsigned Size;
     unsigned ModeSize;
+
+    /// If the memory operand is unsized and there are multiple instruction
+    /// matches, prefer the one with this size.
+    unsigned FrontendSize;
   };
 
   union {
@@ -136,6 +140,10 @@ struct X86Operand : public MCParsedAsmOperand {
     assert(Kind == Memory && "Invalid access!");
     return Mem.ModeSize;
   }
+  unsigned getMemFrontendSize() const {
+    assert(Kind == Memory && "Invalid access!");
+    return Mem.FrontendSize;
+  }
 
   bool isToken() const override {return Kind == Token; }
 
@@ -512,7 +520,7 @@ struct X86Operand : public MCParsedAsmOperand {
   static std::unique_ptr<X86Operand>
   CreateMem(unsigned ModeSize, const MCExpr *Disp, SMLoc StartLoc, SMLoc EndLoc,
             unsigned Size = 0, StringRef SymName = StringRef(),
-            void *OpDecl = nullptr) {
+            void *OpDecl = nullptr, unsigned FrontendSize = 0) {
     auto Res = llvm::make_unique<X86Operand>(Memory, StartLoc, EndLoc);
     Res->Mem.SegReg   = 0;
     Res->Mem.Disp     = Disp;
@@ -521,6 +529,7 @@ struct X86Operand : public MCParsedAsmOperand {
     Res->Mem.Scale    = 1;
     Res->Mem.Size     = Size;
     Res->Mem.ModeSize = ModeSize;
+    Res->Mem.FrontendSize = FrontendSize;
     Res->SymName      = SymName;
     Res->OpDecl       = OpDecl;
     Res->AddressOf    = false;
@@ -532,7 +541,7 @@ struct X86Operand : public MCParsedAsmOperand {
   CreateMem(unsigned ModeSize, unsigned SegReg, const MCExpr *Disp,
             unsigned BaseReg, unsigned IndexReg, unsigned Scale, SMLoc StartLoc,
             SMLoc EndLoc, unsigned Size = 0, StringRef SymName = StringRef(),
-            void *OpDecl = nullptr) {
+            void *OpDecl = nullptr, unsigned FrontendSize = 0) {
     // We should never just have a displacement, that should be parsed as an
     // absolute memory operand.
     assert((SegReg || BaseReg || IndexReg) && "Invalid memory operand!");
@@ -548,6 +557,7 @@ struct X86Operand : public MCParsedAsmOperand {
     Res->Mem.Scale    = Scale;
     Res->Mem.Size     = Size;
     Res->Mem.ModeSize = ModeSize;
+    Res->Mem.FrontendSize = FrontendSize;
     Res->SymName      = SymName;
     Res->OpDecl       = OpDecl;
     Res->AddressOf    = false;